No. If there is no Foo.pm, and you don't use any functionality of Foo.pm then use Foo; will not work and is not considered best practice.

There is no general hierarchical relationship between Foo and Foo::Bar and Foo::Car. Maybe if you wrote the modules, there is some relationship between Foo::Bar and Foo::Car, but in general, this is not true.

one of my colleague said its "best practice" to include 'use Foo' and then include 'use Foo::Bar'

Either there's more to it than you're telling us (perhaps things are set up in your work environment that it does make sense), or it's time to replace your colleague with someone with a basic understanding of Perl.

Went to join the gridlock to see it
Held an eclipse party
Watched a live feed
I cn"t see tge kwubosd to amswr thus
I tried to see it, but 8000 miles of rock got in the way
What eclipse?
Wanted to see it, but they wouldn't reschedule it
Read the book instead